Method of fastening rails to wooden ties upon railroads.



No. 72s,675.- 7 IPATBNTED. MAY 19,1903.

I. COPELAND.

METHOD OI FASIENING RAILS TO- WOODEN TIES IIPON RAILROAD S.

ARPLIOATION FILED, OUT. 17, 1901.

N0 MODEL.

UNITED TATES Patented May 19, 1903.

METHOD OF FASTENING RAILS -TO WOODEN TIES UPON RAILROADS.

SPECIFICATION formingpart of Letters Patent No. 728,675, dated May 19,1903.

Application filed October 17, 1901. Serial No. 78,903. (No model.)

To all whom it may concern:

Be it known that I, IRA COPELAND, of Newton, in the county of Middlesexand State of Massachusetts, have invented a new and useful Improvementin Methods of Fastening Rails to Wooden Ties upon Railroads, of whichthe following, taken in connection withtheaccompanyingdrawings,isaspecification.

My invention relates to a method of fastening the rails to the woodenties upon railroads.

It consists in using spikes of an oval crosssection, in making roundholes for their reception, and in forcing them into said holes in aparticular way.

The object is to so perform the spiking that the ties will last muchlonger than has hitherto been the case and that the spikes shall havegreater tenacity than is obtained by the method generally employed, thusmaterially reducing the cost of maintenance and increasing the safety ofrailroad operation.

My method is illustrated by the accompanying drawings, in which- Figure1 shows one of the spikes in elevation. Fig. 2 is a cross-section of thesame, taken on line 2 2 of Fig. 1. Fig. 3 shows a piece of wood having aspike-hole. The full line indicates a round hole as bored for the spike.The dotted line bounds the space occupied by the spike when driven. Fig.4 shows half a spike-socket such as is formed in the wood by employingmy method. Fig. 5 shows half a spike-socket such as is formed by drivingthe ordinary rectangular spike into solid wood.

The object of this improvement is accomplished by driving a spikewhose'shaft has an elliptical cross-section of uniform size throughoutits length (see Figs. 1 and 2) into a circular bored hole of'properdimensions, (see Fig. 3,) setting the long diameter of the spike in lineof .the. grain of the wood.

In explaining the advantages of this method I will first state somedefects of the method generally employed, which consists in drivingspikes of rectangular cross-section into solid wood. .Such spikes have aflattened point portion terminating in an edge which severs the woodacross the grain for the full width of the spike. If these severingedges were razor-like in keenness, they might not create the havoc whichthey do in actual practice;

but the ordinary processes of. manufacture fail to produce a razor-likecutting edge. Consequently when such spikes are driven into solid woodthey depress and compress successive slivers of wood of much greaterhorizontal extent than the spike-socket until finally in case of eachsliver the point breaks through the sliver. During this operation thesliver will have been broken from its adjoining wood at considerabledistances outside the spike-socket. (See Fig. 5.) The result is that thespike is embedded in a socket whose walls are composed of alternationsof portions of compressed wood and vacant spaces. It should be observedthat the portion of wood which originally occupied the socket-space hasbeen broken through centrally and each half compressed (by thewedgeshaped point portion of the spike) fore and aft against the end ofthe grain of the wood, while there has been no compression laterally.The lack of compression on the sides of the socket naturally results inan imperfect fit, which admits storm -water, which finds its waythroughout the more or less porous socket, tending to produce rapiddecay, necessity of repairs, and insecurity. Myimproved method remediesthese defects to a great extent. It avoids disturbing the texture of thewood, ex-

cept by compression, breaking no wood fibers,

but bending them slightly downward and outward. This compressiongreatlyimproves the texture of the wood which forms the Walls of thespike-socket in all desirable respects. There is compression throughoutthe circumference of the elliptical socket, but it is much greater inthe direction of the long diameter, because the limit of safety is muchgreater in that direction. By the limit of safety I mean the amount ofcompression possible without danger of breaking wood fiber or ofcracking the tie. Some compression is needed on the sides of the sockettransversely with the wood fiber to give forceful impingement all aroundthe spike, so as to increase tenacity and exclude storm-water.

In Fig. 3 the space between the'circular solid line and the ellipticaldotted line represents the amount of compression efiected around thespike. It shows an amount gradually increasing from the sides in allfour directions. Here an important question arises,

viz-z What should be the amount of compression attempted? The results ofnumerous tests hitherto made seem to show that a difference between thediameter of the bored hole and the average diameter of the spike ofone-eighth of an inch gives results of maximum tenacity. Much variationfrom this difference, either above or below, seems to reduce tenacity.As to depth of hole it appears that the deeper the better within thelength of spike driven; but the major portion of the advantages of thismethod may be gained by making the hole of somewhat less depthsay threeor three and one-half inches deep for a spike to be driven five inchesin the wood. The hole should be deep enough to give accurate positionand direction to the spike and to effectually close the spike-socketagainst water.

Fig. 4 illustrates a case where a hole was bored to a depth slightlyless than the spike was driven, allowing the point of the spike toslightly enter solid wood. The spike-socket shown in Fig. 4 is smooth,hard, and firm, closely fitting the spike, leaving no interstices suchas appear in Fig. 5, and showing no broken wood. Experimental tests haveshown that such a spike driven into a hole of proper size had greatertenacity than when driven into the same stick without a hole, and alsothat it had greater tenacity than an ordinary rectangular spike of equalweight driven without a hole.

Another important purpose served by thus embedding the spike in such asocket as is described above is that it increases the eifect of a cementcoating on the spike, (see United States Patent No. 362,940, issued tome May 17, 1887,) inasmuch as it-provides a greater superficial cementedcontact between the metal and the wood.

I have described the spike to be used as having an ellipticalcross-section; but I do not confine myself to an exact ellipse, butwould include all figures nearly approaching an ellipse, even thoughshort straight lines should enter their periphery.

I claim A method. of fastening railroad-rails to wooden ties, consistingof the following steps: first, boring a hole into the tie, whosediameter is slightly less than the short diameter of the spike to beused, second, driving a spike of elliptical cross-section into saidhole, with its long diameter in the line of the direction of the grainof the wood, whereby the greatest amount of frictional holding strain onthe spike is secured, consistent with the preservation of the structureof the Wood, substantially as and for the purposes set forth.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, on this 15th day of October, A.D. 1901.

IRA COPELAND.

Witnesses:

FRANK G. PARKER, WILLIAM EDSON.

